/Engine/Source/Runtime/UMG/Public/Blueprint/WidgetLayoutLibrary.h
Gets the slot object on the child widget as a Canvas Slot, allowing you to manipulate layout information.
static [UCanvasPanelSlot](API\Runtime\UMG\Components\UCanvasPanelSlot) * SlotAsCanvasSlot ( [UWidget](API\Runtime\UMG\Components\UWidget) * Widget )